NUCLEAR CHEMISTRY. Most stable nuclei contain even numbers of both neutrons and protons.

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NUCLEAR CHEMISTRY

Most stable nuclei contain even numbers of both neutrons and protons

THE RATIO OF PROTONS TO NEUTRONS IN C-12 IS 1:1. C-12 IS STABLE.

THE RATIO OF PROTONS TO NEURTONS IN C-14 IS NOT 1:1. C-14 IS AN UNSTABLE NUCLEUS AND WILL BREAK DOWN (DECAY) IN ORDER TO BECOME STABLE. C-14 IS RADIOACTIVE.

RADIOACTIVITY IS THE RLEASE OF ENERGY AND PARTICLES FROM AN UNSTABLE NUCLEUS AS IT DECAYS.

ALPHA DECAY

Radium-226 will alpha-decay to radon-22 

BETA DECAY

BETA DECAY

POSITRON DECAY

TRANSMUTATION REACTION

A nuclear reaction involves the conversion of unstable radioactive element to stable new element with the emission of some radioactive rays. This conversion of unstable radioactive element to stable nuclei is called as nuclear transmutation.

For example; Iodine-131 converts in Xenon-131 with the emission of beta rays.

53I131 → 54Xe131 + −1e0

https://www.youtube.com/watch?v=J8p7OIdyt54

NATURAL DECAY

This type of nuclear transmutation does not require any external initiation; these reactions are spontaneous in nature.

Artificial Transmutation

The conversion of one element into another element by artificial means is called as artificial transmutation.

An aluminum nucleus is bombarded with an alpha particle.There are high energy particles on both sides of the equation.

https://www.youtube.com/watch?v=kHXMiYsFSrU

FISSION REACTION

The splitting of a massive nucleus into two fragments, each with a smaller mass than the original is know as nuclear fission. A typical example of nuclear fission is the splitting of a Uranium-235 nucleus. This is a reaction that is used in nuclear reactors to generate heat by which steam is produced and used to turn turbines that generate electricity.

FUSION REACTION

When two light atomic nuclei fuse to form a heavier nucleus a large amount of energy is released.

Large amount of energy

The sun is a natural fusion reactor.

Nuclear power stations use uranium in fission reactions as a fuel to produce energy. Steam is generated by the heat released during the fission process. It is this steam that turns a turbine to produce electric energy.

Tracers are a common application of radioisotopes. A tracer is a radioactive element whose pathway through which a chemical reaction can be followed. Tracers are commonly used in the medical field and in the study of plants and animals.

MEDICAL TREATMENT

COBALT AND CESIUM ARE USED IN CANCER THERAPY

IODINE -131 IS USED TO TREAT THYROID DISORDERS

RADIOACTIVE ELEMENTS CAN BE USED TO DATE THE AGE OF FOSSILS AND ROCKS.

CARBON -14 IS USED TO DATE ONCE LIVING THINGS, ANIMALS AND PLANTS

URANIUM AND LEAD CAN BE USED TO FIND THE DATE OF ROCKS.

RADIOACTIVITY POSES RISKS

•BIOLOGICAL DAMAGE (BURNS, CANCER, GENETIC DAMAGE)• LONG TERM STORAGE

• ACCIDENTS (FIRES, LEAKS)•POLLUTION OF WATER, SOIL, FOOD, AIR

•TERRORISM

All living things should have the same ratio of 14C and 12C in them as in the air we breathe.

Once a living thing dies, the dating process begins. As long as an organism is alive it will continue to take in 14C; however, when it dies, it will stop. Since 14C is radioactive (decays into 14N),1. the amount of 14C in a dead organism gets less and less over time. 2. measuring the amount of 14C that remains after some has been lost (decayed).